Risk factors for infective endocarditis and outcome of patients with Staphylococcus aureus bacteremia

OBJECTIVE

To investigate the risk factors for Staphylococcus aureus infective endocarditis (SAIE) and 6-month mortality in patients with S aureus bacteremia (SAB).

PATIENTS AND METHODS

This study consisted of patients who were diagnosed as having nosocomial or community-acquired SAB or SAIE between June 1, 2000, and December 31, 2005. Clinical characteristics of patients with SAB were compared with those of patients with SAIE, and predictors of mortality in patients with SAB were analyzed.

RESULTS

The median age of the 132 randomly selected patients with SAB and the 66 patients with SAIE was 66 and 68 years, respectively. Univariable analysis showed that unknown origin of SAB, a valvular prosthesis, a pacemaker, persistent fever, and persistent bacteremia were significantly associated with SAIE. In multivariable analysis, unknown origin of SAB (odds ratio [OR], 4.2; 95% confidence interval [CI], 1.9-9.3; P=.001), a valvular prosthesis (OR, 9.2; 95% CI, 3.2-26.2; P<.001), persistent fever (OR, 3.1; 95% CI, 1.0-9.0; P=.04), and persistent bacteremia (OR, 6.8; 95% CI, 2.3-20.2- P=.001) were independently associated with SAIE. Six- month mortality was 8% in patients with SAB vs 35% in patients with SAIE (OR, 6.5; 95% CI, 2.9- 14.8; P<.001). In univariable analysis, methicillin- resistant S aureus (OR, 7.2; 95% CI, 1.7 - 29.4; P=.005) was significantly associated with 6-month mortality in patients with SAB.

CONCLUSION

Unknown origin of SAB, a valvular prosthesis, persistent fever, and persistent bacteremia were independently associated with SAIE in patients with SAB. In univariable analysis, methicillin-resistant S aureus was associated with 6-month mortality in patients with SAB. S aureus infective endocarditis had a significantly higher mortality than SAB. The optimal management of SAB and SAIE deserves further study.

Galactomannan in bronchoalveolar lavage fluid: a tool for diagnosing aspergillosis in intensive care unit patients

RATIONALE

Invasive aspergillosis (IA) is an important cause of mortality in patients with hematologic malignancies. However, IA appears to be gaining a foothold in the intensive care unit (ICU) in patients without classical risk factors. A recent study described 89 cases of IA in patients in a medical ICU without leukemia or cancer. The diagnosis of IA remains difficult and is often established too late. Galactomannan (GM) is an exo-antigen released from Aspergillus hyphae while they invade host tissue.

OBJECTIVES

This prospective single-center study was conducted to investigate the role of GM in bronchoalveolar lavage (BAL) fluid as a tool for early diagnosis of IA in the ICU.

METHODS

All patients with risk factors identified in our earlier study were evaluated. BAL for culture and GM detection, serum GM levels, and computed tomography scan were obtained for all included patients with signs of pneumonia. Patients were classified as having proven, probable, or possible IA.

MEASUREMENTS AND MAIN RESULTS

A total of 110 patients out of 1,109 admissions were eligible. There were 26 proven IA cases. Using a cutoff index of 0.5, the sensitivity and specificity of GM detection in BAL fluid was 88 and 87%, respectively. The sensitivity of serum GM was only 42%. In 11 of 26 proven cases, BAL culture and serum GM remained negative, whereas GM in BAL was positive.

CONCLUSIONS

IA is common in immunocompromised, critically ill patients. GM detection in BAL fluid seems to be useful in establishing or excluding the diagnosis of IA in the ICU.

Repetitive 18-fluorodeoxyglucose positron emission tomography in isolated polymyalgia rheumatica: a prospective study in 35 patients

OBJECTIVE

To study fluorodeoxyglucose (FDG) deposition in different vascular beds and in the large joints of patients with isolated polymyalgia rheumatica (PMR), and to investigate whether there is a relation between FDG-positron emission tomography (PET) results and risk of relapse.

METHODS

All consecutive patients with isolated PMR underwent a FDG-PET scan before treatment with steroids was started and--if logistics allowed--at 3 and 6 months. PET scans were scored at seven different vascular areas and a total vascular score (TVS) was calculated, ranging from 0 to 21. FDG uptake in the shoulders, the hips and the processi spinosi of the vertebrae was scored as 0 (no uptake), 1 (moderate uptake) or 2 (intense uptake).

RESULTS

Thirty-five patients entered the study. At diagnosis, vascular FDG uptake was noted in 11 patients (31%), predominantly at the subclavian arteries. Mean TVS was low. FDG uptake in the shoulders was noted in 94% of patients, in the hips in 89% and in the processi spinosi of the vertebrae in 51%. The intensity of FDG uptake in the large vessels or in the shoulders, hips or processi spinosi did not correlate with the risk of relapse.

CONCLUSIONS

Only one in three patients has an (moderately) increased vascular FDG uptake, especially in the subclavian arteries. The vast majority has inflammation of shoulders and hips, and half of them have increased FDG-uptake at the processi spinosi. Results of FDG-PET scans in patients with PMR did not correlate with their risk of relapse.

Extremely elevated C-reactive protein

BACKGROUND

C-reactive protein (CRP) is a widely used inflammatory marker. Yet, the clinical significance and outcome of extremely elevated CRP levels are poorly characterized.

METHODS

We collected all patients seen at a university hospital in 2004 with at least one CRP level above 500 mg/l and retrospectively analyzed their electronic files, focusing on patient characteristics, clinical diagnosis, microbiology and vital outcome.

RESULTS

CRP was above 500 mg/l in 130 patients with a median age of 62 years. Patient characteristics, settings, etiologies of inflammation, comorbidities and microbiology varied widely. Infections, mainly bacterial, accounted for 88% of episodes. Outcome was fatal in 36% of all patients and in 61% of patients with active malignancies.

CONCLUSION

A wide variety of infections, especially bacterial, that are generally readily identified account for the majority of instances of extreme CRP elevation. Mortality is high, certainly in oncological patients.

Infective endocarditis: changing epidemiology and predictors of 6-month mortality: a prospective cohort study

AIMS

The aim here is to analyse epidemiology, optimal treatment, and predictors of 6-month mortality in infective endocarditis (IE).

METHODS AND RESULTS

A prospective observational cohort study included 193 patients with 203 episodes of definite IE by the modified Duke criteria. Thirty-four percent of episodes involved prosthetic valves. Thirty-three percent of episodes were nosocomial. Forty-three percent included staphylococci, 26% streptococci, and 17% enterococci. At least one complication occurred in 79% of the episodes and 63% had surgical intervention. Six-month mortality was 22%: 33% for staphylococci, 24% for enterococci, and 8% for streptococci. Seventy-four percent of patients with a contraindication to surgery died when compared with 7% with medical treatment without a contraindication and 16% with surgical treatment. In multivariable logistic regression, predictors of 6-month mortality were age (P=0.03), the causative microorganism (P=0.04), and treatment group (P<0.001).

CONCLUSION

Compared with older series, we observed more prosthetic valve IE, nosocomial IE, and surgery. Staphylococcus aureus and Enterococcus faecalis were predominant microorganisms. Age, staphylococci, and a contraindication to surgery predicted 6-month mortality. Nearly half of deaths had a contraindication to surgery. Six-month mortality did not differ significantly between patients who received surgical treatment as against those who received medical treatment without a contraindication to surgery.

Repetitive 18F-fluorodeoxyglucose positron emission tomography in giant cell arteritis: a prospective study of 35 patients

OBJECTIVE

To study fluorodeoxyglucose (FDG) uptake in the different vascular beds and in the large joints of patients with giant cell arteritis (GCA) at diagnosis, during steroid treatment, and at relapse.

METHODS

All consecutive patients admitted to our department with a diagnosis of GCA underwent FDG-positron emission tomography (PET) scan before treatment with methylprednisolone was started. PET scans were repeated at 3 and 6 months, if the initial PET scans showed vascular FDG uptake. PET scans were scored at 7 different vascular areas and a total vascular score (TVS) was calculated, ranging from 0 to 21.

RESULTS

A total of 35 patients entered the study. At diagnosis, vascular FDG uptake was noted in 29 patients (83%), especially in the subclavian arteries (74%), but also in the aorta (>50%) and up to the femoral arteries (37%). TVS decreased from a mean +/- SD score of 7.9 +/- 5.5 at baseline to 2.4 +/- 3.5 on repeat PET scan at 3 months (P < 0.0005), but did not further decrease at 6 months. The patients who relapsed had similar earlier decreases of TVS compared with those who did not relapse. FDG uptake in the shoulders at diagnosis correlated significantly with the presence of polymyalgia rheumatica (P = 0.005).

CONCLUSION

FDG uptake in the large vessels is a sensitive marker for GCA, which can involve the larger thoracic, abdominal, and peripheral arteries. Polymyalgia rheumatica symptoms in patients with GCA correlate with (peri)synovitis of the shoulders. Relapses of GCA cannot be predicted by results of former PET scintigraphies.

Idiopathic renal infarction

BACKGROUND

Renal infarction may be an underrecognized disorder. Classical teaching holds that cardioemboli, notably in the setting of arterial fibrillation, are responsible. The expanding use of contrast enhanced computed tomography (CT) in patients with acute abdomen may change the spectrum of renal infarction.

METHODS

Twenty-seven consecutive patients presenting to a single university hospital with nontraumatic CT-documented acute renal infarction were studied and stratified according to the presence or absence of cardiac disease, either obvious at presentation or detected during work-up.

RESULTS

Eleven patients (41%) had obvious cardiac disease, including atrial fibrillation in all but one. Sixteen patients (59%) had no discernible structural or arrhythmic cardiac disease and were classified as idiopathic group. Patients in the idiopathic group were significantly younger (median age in years [interquartile range]: 48 [41-53] versus 75 [53-82] years, P = .003) and, besides smoking, had fewer traditional cardiovascular risk factors.

CONCLUSION

Acute renal infarction may occur in individuals of middle age without risk factors for cardioembolism. In patients with renal colic without lithiasis the diagnosis of renal infarction should be considered especially if serum lactate dehydrogenase is elevated, even in the absence of atrial fibrillation.

Cancer presenting as fatal pulmonary tumour embolism

Rapidly fatal pulmonary tumour embolism is a rare complication of malignancy, and often presents as progressive dyspnea without obvious cause. We describe two cases presenting with a dramatic clinical picture of lactic acidosis and cardiopulmonary arrest soon after admission on ICU. The first patient was a 29-year old woman with a breast cancer seeming in remission who was admitted with rapidly increasing dyspnea since two weeks. The second patient was a 46-year old woman with HIV and no history of malignancy, who developed dyspnea and lactic acidosis over the course of a few days while she was investigated for an occipital brain lesion. Both patients died soon after admission and massive tumour emboli were found on autopsy. Breast cancer was the origin of the emboli in both cases. Symptoms were out of proportion to the initial physical cardiopulmonary findings and radiographic features. Clinical signs of pulmonary tumour embolism are non-specific and subacute. Prognosis is poor and definite diagnosis is usually made post-mortem. Solid malignancies such as breast cancer account for most of the cases. Pulmonary tumour embolism should be considered in critically ill patients with unexplained hypoxemia and lactic acidosis, mild or no radiological abnormalities and fast clinical deterioration. It may occur in young patients and in patients without history of malignancy.

The diagnostic spectrum of unintentional weight loss

Significant and documented involuntary weight loss in adults frequently poses a diagnostic challenge to the clinician. We summarize published series on the etiologies and the outcomes of involuntary weight loss and use these data to formulate a proposal for a diagnostic work-up. Simple, non-invasive screening tests, embarking from thorough history-taking and clinical examination, are advocated first. Additional testing should be directed towards areas of concern raised by this initial evaluation. If a well-thought-out baseline examination is reassuring and fails to provide further clues, a strategy of watchful waiting with close clinical follow-up is preferred to a blind pursuit of additional, more invasive, or expensive investigations.

Survival after a lethal dose of arsenic trioxide

A case of a 27-year-old woman who ingested 9000 mg arsenic trioxide (As2O3) is reported. Classical symptoms of an acute arsenicum (As) poisoning such as gastrointestinal cramps, vomiting, diarrhea, ECG changes and disturbed liver function tests were observed. The absorption of the ingested As was minimalized by a continuous gastric irrigation with highly concentrated NaHCO3 and intestinal cleansing with NaHCO3 and polyethyleneglycol was performed. Forced diuresis, BAL (2,3-dimercaptopropanol) and DMSA (meso-2,3-dimercaptosuccinic acid) were started and therapy to enhance the formation of methylated As derivatives, which are potentially less toxic and which can be excreted more easily, was then administered. The patient survived this massive dose of ingested inorganic As with only polyneuropathy one year later.

Contribution of (18)fluoro-deoxyglucose positron emission tomography to the work-up of patients with fever of unknown origin

Background: Recent studies have suggested that (18)fluoro-deoxyglucose (FDG) positron emission tomography (PET) may be useful in the work-up of patients with fever of unknown origin (FUO), but its exact diagnostic yield has not been established. Methods: From January 1999 through December 2001, 74 (67%) of 110 prospectively collected patients who fulfilled the revised criteria of classic FUO underwent a FDG-PET scan. The diagnostic yield of this technique was assessed after diagnostic work-up and follow-up. Abnormal FDG-PET scans that pointed to the final diagnosis were categorized as helpful; all other scans were considered noncontributory. Results: A final diagnosis was established in 39 (53%) of the 74 patients who underwent FDG-PET. Fifty-three (72%) of the 74 FDG-PET scans were abnormal; 19 scans (36% of the abnormal scans or 26% of the total number of scans) were helpful. In the 39 patients with a final diagnosis, 49% of the scans were helpful. A diagnosis was established in 31 (58%) of the 53 patients with an abnormal scan and in 8 (38%) of the 21 patients with a normal scan (P=0.2). Baseline clinical variables (age and sex, as well as periodicity, duration, and height of the fever) and inflammatory parameters (erythrocyte sedimentation rate, C-reactive protein, and hemoglobin) did not predict the usefulness of FDG-PET. Conclusions: FDG-PET contributed positively to the diagnosis in a quarter of our patients with classical FUO. This number is lower than that found in previous studies. Yet, against the background of the wide array of heterogeneous disorders that make up the FUO spectrum and the low number of final diagnoses established (in only 53% of cases), the diagnostic yield of FDG-PET is encouraging. Therefore, the use of FDG-PET should be considered whenever a baseline work-up fails to reveal the cause of a prolonged, febrile illness.

Nurses' attitudes toward pain treatment with opioids: a survey in a Belgian university hospital

AIM

To investigate nurses' attitudes toward pain treatment with opioids in a Belgian university hospital.

METHOD

A cross-sectional, descriptive study design was used. The randomised sample included 350 nurses working in the University Hospital Leuven, Belgium. Non-response was 10.9%. Nurses' attitudes were explored by a structured questionnaire. The score on the opioid attitude scale (OAS) varied between 9 and 45.

RESULTS

Despite a neutral to positive score on the OAS (mean=69.4%), nurses had clearly negative attitudes towards the use of opioids during a diagnostic phase and the risk of possible addiction. These negative attitudes can hinder adequate pain treatment.

Pain during bone marrow aspiration: prevalence and prevention

The prevalence, intensity, determinants and prevention of pain during bone marrow aspiration (BMA) in adults are not well defined. In the first part of this prospective study (observational phase), 132 adult hematological patients undergoing BMA after local anesthesia scored the procedural pain by means of a visual analogue scale (VAS). Moderate to severe pain was defined as a VAS score exceeding 30 mm. Eighty-six percent reported procedural pain. The VAS score (mean+/-SEM) was 27.2+/-2.1 mm. Thirty-six percent of patients graded the pain as moderate to severe. In a linear regression analysis, VAS score correlated positively with the duration of the procedure (P=0.029) and negatively with the age of the patient (P=0.006). In the second part of the study (interventional phase), 100 patients were randomized to 50 mg tramadol or placebo, given orally at least one hour before BMA. VAS scores during aspiration were significantly lower in tramadol recipients versus placebo recipients (16.5+/-3.0 mm and 28.8+/-3.4 mm, respectively, P=0.003). Pretreatment with tramadol reduced the percentage of patients with at least moderate pain from 40% to 20% (P=0.029). Four tramadol and 3 placebo recipients reported side effects (dizziness or sedation). In conclusion, notwithstanding local anesthesia, the great majority of adult hematological patients experience transient pain during BMA that is of at least moderate intensity in over a third. Pretreatment with tramadol lowers pain intensity significantly and is well tolerated.

From prolonged febrile illness to fever of unknown origin: the challenge continues

BACKGROUND

Epidemiological changes and the ongoing expansion of the diagnostic armamentarium warrant a regular update of the spectrum of diseases that present as prolonged febrile illnesses.

METHODS

We prospectively collected a series of 290 immunocompetent patients referred to our university hospital between 1990 and 1999 with a febrile illness (temperature >38.3 degrees C) of uncertain cause, lasting at least 3 weeks. Patients were categorized in 4 groups according to the timing of diagnosis: early diagnosis (within 3 in-hospital days or 3 outpatient visits), intermediate diagnosis (between days 4 and 7), late diagnosis (after day 7), and no diagnosis during index contact or follow-up.

RESULTS

A final diagnosis was established early in 67 patients (23.1%), intermediate in 38 (13.1%), and late in 87 (30.0%). In the remaining 98 (33.8%), no diagnosis was made. The cause of the fever remained obscure in 50 (47.6%) of 105 patients with episodic fever vs 48 (25.9%) of 185 patients with continuous fever (P<.001). Among the 192 patients with a final diagnosis, noninfectious inflammatory diseases represented the most prevalent diagnostic category (35.4%), surpassing infections (29.7%), miscellaneous causes (19.8%), and malignancies (15.1%). Fourteen disorders accounted for over 59% of diagnoses, whether diagnosis was reached early, intermediate, or late. Hematological malignancies made up 11.5% of diagnoses, but were responsible for 14 (58.3%) of the 24 fatalities related to the febrile illness. Of the 80 patients discharged alive without diagnosis and for whom follow-up was available, 3 died, but the deaths were considered to be unrelated to the feverish illness.

CONCLUSIONS

Prolonged febrile illnesses remain a diagnostic challenge. Despite the technological progress of the late 20th century, the origin of the fever remains elusive in many patients, especially in those with episodic fevers. Noninfectious inflammatory diseases emerge as the most prevalent diagnostic category.

[Weight loss, joint pain and abdominal lymphadenopathy as signs of sarcoidosis, but also of Whipple's disease]

Two patients, a woman aged 66 and a man aged 56 years, with an inflammatory syndrome, weight loss, joint pain and abdominal lymphadenopathy received long-term treatment with corticosteroids for alleged sarcoidosis. No long-term remission was induced and the patients were referred for a second opinion. Eventually the diagnosis of Whipple's disease was established 5 years after the appearance of the first symptoms in the case of the female patient and 4 years after in the case of the male patient. Both patients showed a marked clinical improvement after treatment with trimethoprim-sulfamethoxazole. An atypical presentation of alleged sarcoidosis should suggest the possibility of Whipple's disease, especially in the case of gastrointestinal symptoms and the failure to respond to corticosteroids, and warrants duodenal biopsy. The presence of granulomas with an elevated angiotensin-converting enzyme level is not pathognomonic for sarcoidosis. It is vitally important to distinguish the two disorders, as Whipple's disease is an infectious disorder that requires antibiotic therapy to prevent a fatal outcome.

Fever of unknown origin in adults: 40 years on

A revision of the criteria of fever of unknown origin (FUO), established in 1961, is desirable because of important evolutions in medical practice and the emergence of new patient populations. The development of rapid laboratory tests and powerful diagnostic tools, such as ultrasonography, computed tomography and magnetic resonance imaging often makes hospitalization unnecessary and new categories of patients such as those with HIV infection, neutropenia, immunosuppression and nosocomial illness require an approach different from classical FUO. The more then 200 reported causes of FUO can be classified into four diagnostic categories; infections, tumours, noninfectious inflammatory diseases (NIID) and miscellaneous. A uniform classification system is highly wanted to allow comparison between different series. The reports of the 1990s show slight changes in the distribution of causes, namely less infections, less tumours, more NIID and more undiagnosed cases. A uniform diagnostic strategy cannot be determined. The initial investigation should be directed by potentially diagnostic clues revealed by extensive history, meticulous physical examination and a standard set of laboratory tests. 18Fluoro-deoxy-glucose-positron-emitted-tomography is a new valuable total body scintigraphy in the search for the site of origin of the fever. In view of the rather good long-term prognosis, a wait-and-see strategy may be more appropriate than a systematic staged approach. Elderly patients and patients with episodic fever represent two specific groups of classical FUO that require a distinct approach. HIV-associated, nosocomial and neutropenic FUO should be considered as separate clinical entities.

Microscopic haematuria in giant cell arteritis

Giant cell arteritis (GCA) is traditionally considered to spare the kidney, although an uncontrolled study reported microscopic haematuria in 10 out of 30 patients with GCA. To study the frequency and the characteristics of microscopic haematuria in GCA, we retrospectively studied 42 patients with biopsy-proven GCA, 39 patients with polymyalgia rheumatica (PMR) and 62 control patients >or=60 years of age, admitted to the general internal medicine unit. Patients with pyuria, significant bacteriuria or a known haematuric disorder were excluded. Microscopic haematuria was defined as the presence of >5 red blood cells (RBC) per high-power field (sediment counts) or of >8 RBC/microl (direct counting). Microscopic haematuria was present at presentation in 47.6% of the GCA patients, versus 17.9% of the PMR patients (P = 0.005) and 21.0% of the control patients (P = 0.008). Urinary RBC were predominantly dysmorphic in all GCA patients in whom RBC morphology was assessed (n = 7). Presenting symptoms, renal function, arterial blood pressure and degree of leukocyturia did not differ significantly between GCA patients with or without haematuria. After the initiation of corticosteroid therapy, microscopic haematuria was no longer detectable in 25 of 35 GCA patients (71.4%). Microscopic haematuria of renal origin is frequent but generally benign in patients with GCA. Its presence, if unassociated with blood pressure elevation or renal function deterioration, helps to rule in rather than to rule out the diagnosis of GCA. In the typical setting invasive urologic and nephrologic work-up may not be warranted.

Progressive bouts of acute abdomen: pet the peritoneum

The recent discovery of the mutated gene responsible for Familial Mediterranean Fever (FMF) is supposed to facilitate its diagnosis which up till now is a clinical one because there are no specific laboratory tests. The sensitivity of genetic testing is limited because these tests search only for known mutations. In this case report we describe a patient with periodic abdominal pain in whom the diagnosis of FMF was wrongly discarded because of lack of a durable effect of colchicine and negative genetic testing. Diffuse peritoneal inflammation was nicely demonstrated by a FDG-PET (fluoro-deoxy-glucose positron-emission tomography) performed during a typical crisis. We discuss the possible diagnostic pitfalls and conclude that a crisis-PET might upgrade the level of diagnostic certainty in equivocal cases.

Thrombocytopenia and prognosis in intensive care

OBJECTIVE

To study the incidence and prognosis of thrombocytopenia in adult intensive care unit (ICU) patients.

DESIGN

Prospective observational cohort study.

SETTING

The medical ICU of a university hospital and the combined medical-surgical ICU of a regional hospital.

PATIENTS

All patients consecutively admitted during a 5-month period.

INTERVENTIONS

Patient surveillance and data collection.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was ICU mortality. Data of 329 patients were analyzed. Overall ICU mortality rate was 19.5%. A total of 136 patients (41.3%) had at least one platelet count <150 x 10(9)/L. These patients had higher Multiple Organ Dysfunction Score (MODS), Simplified Acute Physiology Score (SAPS) II, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores at admission, longer ICU stay (8 [4-16] days vs. 5 [2-9] days) (median [interquartile range]), and higher ICU mortality (crude odds ratio [OR], 5.0; 95% confidence interval [CI], 2.7-9.1) and hospital mortality than patients with daily platelet counts >150 x 10(9)/L (p < .0005 for all comparisons). Bleeding incidence rose from 4.1% in nonthrombocytopenic patients to 21.4% in patients with minimal platelet counts between 101 x 10(9)/L and 149 x 10(9)/L (p = .0002) and to 52.6% in patients with minimal platelet counts <100 x 10(9)/L (p < .0001). In all quartiles of admission APACHE II and SAPS II scores, a nadir platelet count <150 x 10(9)/L was related with a substantially poorer vital prognosis. Similarly, a drop in platelet count to < or =50% of admission was associated with higher death rates (OR, 6.0; 95% CI, 3.0-12.0; p < .0001). In a logistic regression analysis with ICU mortality as the dependent variable, the occurrence of thrombocytopenia had more explanatory power than admission variables, including APACHE II, SAPS II, and MODS scores (adjusted OR, 4.2; 95% CI, 1.8-10.2).

CONCLUSIONS

Thrombocytopenia is common in ICUs and constitutes a simple and readily available risk marker for mortality, independent of and complementary to established severity of disease indices. Both a low nadir platelet count and a large fall of platelet count predict a poor vital outcome in adult ICU patients.

Outcome and one year follow-up of intra-arterial staphylokinase in 191 patients with peripheral arterial occlusion

Wild-type or equipotent variants of recombinant staphylokinase (rSak) were given intra-arterially (as a 2 mg bolus injection followed by an infusion of 1 mg/h or 0.5 mg/h overnight, with concomitant heparin [1000 IU/h]) to 191 patients of less than 80 years (62 +/- 1 years, mean +/- SEM), with a peripheral arterial occlusion (PAO) of less than 120 days (mean 14 +/- 1 days, median 11 days, 5 to 95 percentiles 3 to 30 days). Ninety nine patients presented with acute or subacute ischemia, 57 with severe claudication, 33 with chronic rest pain and 2 with gangrene. Occlusion occurred in 122 native arteries and in 69 grafts. Revascularization was complete in 83 percent (158/191), partial in 13 percent (24/191) and absent in 4 percent (7/191) after administration of 12 +/- 0.5 mg rSak over 14 +/- 0.7 h. Complete revascularization of acute occlusions of popliteal or more distal arteries was less frequent (60 percent, 15/25) than of acute occlusions of more proximal native arteries (95 percent, 37/39, p <0.001) or grafts (89 percent, 50/56, p = 0.005). Additional endovascular procedures were performed in 47 percent and subsequent elective bypass surgery in 23 percent of patients. Major bleeding occurred in 12 percent (23/191), one month mortality was 3.1 percent (6/191) and one year mortality was 6.9 percent (12/174). However, four patients (2.1 percent) had an intracranial bleeding following therapy: a 85 year old woman with severe diabetic arteriopathy, who was included in violation of the protocol, a 79 and a 74-year-old woman and a 74-year-old man, all with severe hypertension and limb threatening ischemia; these four patients died within two months after treatment. Amputations were performed within the first year in 16 of 162 surviving patients (9.8 percent): in 7 percent (7/96) with an occluded native artery and 14 percent (9/66) with an occluded graft (p = 0.19). No significant difference in lysis rate, one month mortality or one year amputation-free survival was observed in occlusions of recent onset (< or =14 days, n = 126) as compared to occlusions of longer duration (>14 days, n = 65). Treatment was interrupted prematurely in 4 patients because of a suspected allergic reaction. Fibrinogen levels remained unaffected during treatment (3.3 +/- 0.1 g/l before vs. 3.3 +/- 0.1 g/l after infusion, n = 167). In conclusion, rSak appears to be a highly effective thrombolytic agent in patients with PAO, resulting in a low one month mortality (3.1 percent) and a high one year amputation free survival (84 percent), with an acceptable incidence of major bleedings, but with occasional fatal intracranial hemorrhages.

[Staphylokinase for a better thrombolytic treatment of heart and platelet diseases]

Staphylokinase is a plasminogen activator of bacterial origin with pronounced fibrin specificity. The first clinical studies suggest that recombinant staphylokinase (Sak) constitutes an effective thrombolytic agent in the treatment of patients with myocardial infarction or peripheral arterial occlusion. Also in an animal ischemic stroke model Sak has produced promising results. Despite its fibrin specificity life-threatening bleeding still may occur. Sak induces neutralizing antibodies that may interfere with renewed administration. Therefore, recombinant variants have been engineered that are less antigenic while preserving thrombolytic properties.

Duodenogastroesophageal reflux and esophageal mucosal injury in mechanically ventilated patients

BACKGROUND & AIMS

Esophagitis has been reported to be the most frequent cause of upper gastrointestinal bleeding in intensive care patients. The mechanisms causing esophagitis are unclear. The aim of this study was to measure esophageal acid and bile reflux and to examine the relationship between reflux and mucosal injury in mechanically ventilated patients.

METHODS

Twenty-five critically ill, mechanically ventilated patients with nasogastric tubes were prospectively included for 24-hour esophageal pH and duodenogastroesophageal bile reflux studies (Bilitec 2000 system). All patients received acid-suppressive therapy for stress ulcer prophylaxis with ranitidine. On the day before the study, patients underwent esophageal endoscopy to determine the presence or absence of esophagitis.

RESULTS

After approximately 5 days of mechanical ventilation, 12 patients (48%) had erosive esophagitis, 2 patients had pathological acid reflux, and 12 patients had pathological bile reflux. The presence of esophagitis was significantly associated with pathological bile reflux (P = 0.017, Fisher exact test). The severity of esophagitis was significantly correlated with the volume of gastric residual volume and with increasing times of bile reflux. The latter was significantly correlated with the number of organ failures.

CONCLUSIONS

Despite acid-suppressive therapy, esophagitis is a frequent finding in critically ill patients after less than a week of mechanical ventilation. In these patients, besides mechanical irritation by the nasogastric tube, chemical injury caused by duodenogastroesophageal reflux seems to have a major role in the pathogenesis of esophageal mucosal lesions.

Intravenous thrombolysis with recombinant staphylokinase versus tissue-type plasminogen activator in a rabbit embolic stroke model

BACKGROUND AND PURPOSE

Timely intravenous administration of recombinant tissue-type plasminogen activator (alteplase, rTPA) to patients with evolving ischemic stroke improves neurological outcome. The present study was designed to compare the effects of rTPA and recombinant staphylokinase (Sak), a highly fibrin-specific thrombolytic agent, in an experimental model of rabbit embolic stroke.

METHODS

Groups of 5 to 12 rabbits were given intravenous saline or heparin and aspirin with, in addition, either Sak (1 or 2 mg/kg infused over 30 minutes or 2 mg/kg injected over 1 minute) or rTPA (3 or 6 mg/kg infused over 30 minutes or 6 mg/kg injected over 1 minute). Infusions were started 15 minutes after selective injection of standardized 125I-fibrin labeled rabbit plasma clots into the internal carotid artery.

RESULTS

Mean clot lysis over 60 minutes increased from 3.8% after saline to between 27% and 44% after Sak regimens (P = .0001 versus control) and to between 15% and 34% after rTPA regimens (P = .0001). Median volume of the ischemic lesion at 5 hours decreased from 190 mm3 after saline to between 11 and 17 mm3 after Sak (P = .02) and to between 0.5 to 54 mm3 after rTPA (P = .04). Mean neurological impairment at 5 hours (on a scale of 0 to 3) decreased from 2.3 after saline to between 1.3 to 1.6 after Sak (P = .003) and to between 1.1 to 1.9 after rTPA (P = .02). At the highest doses used, fibrinogen depletion was marginal with Sak but total with rTPA. Marked prolongation of car puncture and cuticle bleeding times was only observed after bolus administration of rTPA.

CONCLUSIONS

In the present rabbit model of embolic stroke, Sak was significantly more fibrin-specific than rTPA and at least as effective in lysing arterial emboli and limiting ischemia and neurological impairment.

Randomized coronary patency trial of double-bolus recombinant staphylokinase versus front-loaded alteplase in acute myocardial infarction

One hundred two patients with evolving myocardial infarction of 6 hours' duration were given aspirin and intravenous heparin and randomly allocated to intravenous front-loaded, weight-adjusted rTPA administration over a 90-minute period (52 patients) or to two 15 mg doses of recombinant staphylokinase, 30 minutes apart (50 patients). Thrombolysis in Myocardial infarction (TIMI) perfusion grade 3 at 90 minutes was achieved in 68% (95% confidence interval, 55% to 81%) of patients treated with staphylokinase versus 57% (95% confidence interval, 43% to 72%) of patients treated with rTPA (p = not significant). Double-bolus staphylokinase was significantly more fibrin-specific than accelerated rTPA with residual fibrinogen at 90 minutes of 105% +/- 4.1% and 68% +/- 7.5%, respectively (p < 0.0001). Thirteen patients in each study group underwent angioplasty of the culprit coronary artery within the first 24 hours because of suboptimal recanalization (TIMI < 3). In the patients without prior coronary intervention, TIMI 3 at 24 hours was 100% after staphylokinase administration (n = 35) versus 79% after rTPA (n = 34) (p = 0.005). The distribution of inhospital events did not significantly differ between both groups. One patient receiving rTPA died in the hospital from ischemic stroke. Staphylokinase administration did not induce allergic reactions, but significant staphylokinase-neutralizing activity (> 5 micrograms/ml) and specific anti-staphylokinase IgG developed in 73% of patients after 2 weeks. Thus two 15 mg doses of staphylokinase induce early, complete, and sustained coronary artery patency at least as frequently as accelerated rTPA without associated fibrinogen degradation but with subsequent induction of circulating neutralizing antibodies.

Recombinant staphylokinase variants with altered immunoreactivity. IV: Identification of variants with reduced antibody induction but intact potency

BACKGROUND

The thrombolytic potency and antibody induction of selected variants of recombinant staphylokinase (SakSTAR), including SakSTAR(K74) with Lys74, SakSTAR(E75) with Glu75-, SakSTAR(EER) with Glu38, Glu75, and Arg77, and SakSTAR(K74ER) with Lys74, Glu75, and Arg77 replaced by Ala, were studied.

METHODS AND RESULTS

In rabbits, SakSTAR(74) and SakSTAR(EER) elicited significantly less circulating neutralizing activity than SakSTAR and SakSTAR(E75) (P = .005 and P = .0002 versus SakSTAR, respectively). In baboons, SakSTAR(K74) induced significantly fewer antibodies than wild-type SakSTAR (P < .05). Intra-arterial administration in patients with peripheral arterial occlusion of SakSTAR(K74) (n = 11) or SakSTAR(K74ER) (n = 6) induced significantly fewer circulating neutralizing antibodies [median values and interquartile ranges, 20 (3.8 to 26) and 2.4 (0.2 to 59) micrograms compound neutralized/mL plasma after 3 to 4 weeks (P = .01 and P = .035 versus SakSTAR, respectively)] than SakSTAR (n = 9) [median value and interquartile range, 93 (24 to 110) micrograms compound neutralized/mL plasma]. Overt neutralizing antibody induction (> 10 micrograms compound neutralized/mL plasma) occurred in all 9 patients given wild-type SakSTAR, in 6 of the 11 SakSTAR(K74ER) patients (P = .038 versus SakSTAR), and in 2 of the 6 SakSTAR(K74ER) patients (P = .011 versus SakSTAR).

CONCLUSIONS

SakSTAR(K74), a variant of recombinant staphylokinase with a single substitution of Lys74 with Ala, and SakSTAR(K74), with Lys74, Glu75, and Arg77 substituted with Ala, have intact thrombolytic potencies but induce significantly less antibody formation in patients.

Procoagulant properties of intravenous staphylokinase versus tissue-type plasminogen activator

The fibrin-specificity and procoagulant effects of recombinant staphylokinase (Sak42D) were compared with those of recombinant tissue-type plasminogen activator (rt-PA) in patients with acute myocardial infarction. Plasma samples were obtained at baseline and at 25 and 90 min, from 24 patients who were randomly assigned to a double bolus (15 mg each, 30 min apart) administration of Sak42D or to accelerated weight-adjusted rt-PA (maximum of 100 mg over 90 min). Baseline levels of fibrinopeptide A (FPA), prothrombin fragment 1 + 2 and thrombin-antithrombin III complex (TAT) were comparable in the Sak42D and rt-PA groups (p > or = 0.6). In patients treated with Sak42D, plasma levels of FPA, prothrombin fragment 1 + 2 and TAT did not markedly increase during treatment (p = 0.06, p = 0.4 and p = 0.03, respectively). In contrast, during administration of rt-PA the levels of FPA, prothrombin fragment 1 + 2 and TAT increased significantly over baseline (p = 0.003, p < 0.0001 and p = 0.001, respectively). As a result, the levels of all three procoagulant parameters were significantly lower during treatment with Sak42D as compared to rt-PA. Thus, FPA levels in the Sak42D group (median values) were 40 ng/ml at 25 min and 11 ng/ml at 90 min, as compared to 88 ng/ml and 50 ng/ml in the rt-PA group (p = 0.0007 and p = 0.009, respectively). Prothrombin fragment 1 + 2 levels in the Sak42D group were 1.3 nM at 25 min and 1.2 nM at 20 min, as compared to 11 nM and 5.3 nM in the rt-PA group (both p < 0.0001). TAT levels were 4.7 ng/ml at 25 min and 6.2 ng/ml at 90 min in the Sak42D group, with corresponding values of 16 ng/ml and 9.6 ng/ml in the rt-PA group (p = 0.02 and p = 0.03, respectively). In the patients treated with Sak42D, no significant systemic fibrinolytic activation was observed, as revealed by unaltered levels of clottable fibrinogen, plasminogen and alpha 2-antiplasmin up to 90 min after the start of therapy. In contrast, the corresponding residual levels at 90 min in patients treated with rt-PA decreased to (mean +/- SEM; n = 12) 62 +/- 6%, 45 +/- 5% and 52 +/- 10%, respectively (all p < or = 0.01 versus the Sak42D group). These data confirm the high degree of fibrin-specificity of Sak42D and demonstrate that this is associated with significantly less generation of procoagulant activity in plasma after intravenous administration in patients with acute myocardial infarction.

A pilot study on bolus administration of recombinant staphylokinase for coronary artery thrombolysis

Recombinant staphylokinase (Sak) is a highly fibrin-specific thrombolytic agent but the optimal dose and mode of administration remain to be defined. Intravenous (i.v.) infusion over 5 min of 20 mg Sak in 12 patients with acute myocardial infarction induced complete coronary patency (TIMI perfusion grade 3) in 7 patients (58%) within 60 min. In 3 of the 5 patients with no or suboptimal flow (TIMI grade 0, 1 or 2) at 60 min, an additional 10 mg i.v. bolus of Sak resulted in TIMI grade 3 flow at 90 min. No major treatment-related complication occurred. Residual fibrinogen and alpha 2-antiplasmin levels at 90 min were 110 +/- 6.0% and 98 +/- 4.1% (mean +/- SEM) of baseline, respectively. Median antibody-related Sak-neutralizing activity was low at baseline (0.0 microgram/ml) and after 1 week (0.5 microgram/ml) but increased from day 10 on (to 4.0 micrograms/ml). Thus, bolus thrombolysis with Sak may induce efficient coronary artery recanalization while preserving circulating fibrinogen and alpha 2-antiplasmin. Comparative trials of coronary thrombolysis with double-bolus Sak appear to be warranted.

Recombinant staphylokinase variants with altered immunoreactivity. II: Thrombolytic properties and antibody induction

BACKGROUND

The substitution variants K35A,E38A,K74A, E75A,R77A (SakSTAR.M38) and K74A,E75A,R77A,E80A, D82A (SakSTAR.M89) of recombinant staphylokinase (SakSTAR) with reduced antibody reactivity were assayed for thrombolytic potency and antibody induction in animal models and in patients.

METHODS AND RESULTS

In a 125I-fibrin-labeled pulmonary embolism model in the hamster, the doses giving 50% clot lysis in 90 minutes were 25 micrograms/kg for SakSTAR, 85 micrograms/kg for SakSTAR.M38, and 90 micrograms/kg for SakSTAR.M89. In rabbits with 125I-fibrin-labeled plasma clots incorporated into extracorporeal arteriovenous loops, lysis within 2 hours was 76 +/- 18% (mean +/- SD, n = 28) with 400 micrograms/kg SakSTAR, 53 +/- 13% (n = 8) with 1000 micrograms/kg SakSTAR.M38, and 39 +/- 13% (n = 6) with 800 micrograms/kg SakSTAR.M89. When groups of eight rabbits were immunized by intravenous administration of 0.2 to 1.0 micrograms/kg compound followed by subcutaneous injection of 0.4 mg in Freund's adjuvant at 2, 3, and 5 weeks, SakSTAR.M38 and SakSTAR.M89 elicited markedly less circulating neutralizing activity, compared with SakSTAR, when determined at 6 weeks (neutralizing 6.1 +/- 3.0 and 4.9 +/- 1.3 micrograms compound/mL plasma, respectively, versus 20 +/- 17 micrograms/mL; P = .02 and P = .01, respectively) and induced significantly less resistance to thrombolysis (residual thrombolytic potency producing 59 +/- 25% and 39 +/- 12% lysis, respectively, versus 8.5 +/- 5.7%; P = .008 and P = .006, respectively). In patients with peripheral arterial occlusion, intra-arterial administration of SakSTAR.M38 (n = 4) or SakSTAR.M89 (n = 4) induced significantly fewer circulating neutralizing antibodies (P = .03) and specific IgG (P = .01) at 2 to 3 weeks than SakSTAR (n = 8).

CONCLUSIONS

SakSTAR.M38 and SakSTAR.M89 induce less antibody formation and might constitute preferred agents for thrombolytic therapy in humans.

Comparative antigenicity of recombinant wild-type staphylokinase (SakSTAR) and a selected mutant (SakSTAR.M38) in a baboon thrombolysis model

Staphylokinase, a bacterial plasminogen activator, is a potent, highly fibrin-specific but antigenic thrombolytic agent in humans. In an effort to attenuate the antigenicity of wild-type staphylokinase (SakSTAR variant), 2 of its 3 immunodominant epitopes were altered by substituting clusters of 2 or 3 charged amino acids with alanine, yielding the mutant SakSTAR.M38 (K35A, E38A, K74A, E75A, R77A), which was less antigenic in inbred New Zealand White rabbits. In the present study, groups of 6 baboons (Papio hamadryas) were randomized to SakSTAR (group 1) or SakSTAR.M38 (group 2). The thrombolytic potencies of 50 micrograms/kg compound at baseline, assessed in an extracorporeal thrombosis model, were similar: 77 +/- 2.9% (mean +/- SEM) clot lysis in group 1 and 83 +/- 3.6% in group 2. Groups 1 and 2 were immunized subcutaneously at 2, 3, and 5 weeks with 500 micrograms SakSTAR or SakSTAR.M38, respectively. From 6 weeks, group 1 developed significantly more antibody-related neutralizing activity than group 2 (maximal titer at 8 weeks of 100 +/- 23 micrograms SakSTAR and of 22 +/- 7.1 micrograms SakSTAR.M38 neutralized per milliliter of plasma, respectively). Neutralizing activities subsequently decreased gradually to 10-20% of peak values at 18 weeks. At 6 weeks, both groups were resistant to thrombolysis with 50 micrograms/kg of either compound. Rechallenge at 18 weeks with 250 micrograms/kg of the immunizing compound showed a significantly better recovery of the thrombolytic potency of SakSTAR.M38 (68 +/- 4.5% clot lysis) than of SakSTAR (39 +/- 5.3% clot lysis). Neither agent degraded fibrinogen or depleted alpha 2-antiplasmin. Therefore, SakSTAR.M38 is comparably active and fibrin-specific but less antigenic than wild-type SakSTAR. These findings in outbred primates confirm and extend earlier observations in inbred rabbits and provide a basis for the further development of staphylokinase variants with reduced antigenicity in humans.

Comparative effects of staphylokinase and alteplase in rabbit bleeding time models

BACKGROUND

The pathogenesis of bleeding associated with thrombolytic therapy remains largely unknown, although spontaneous bleeding appears to correlate with bleeding time prolongation. Here, the comparative effects on cuticle bleeding times (CBT) and ear puncture bleeding times (EBT) of recombinant staphylokinase (Sak) and alteplase (recombinant tissue-type plasminogen activator, rt-PA) at equivalent doses, alone and in combination with aspirin and heparin, were studied in rabbits.

METHODS AND RESULTS

Groups of 4 to 9 rabbits were allocated to one of the 8 following intravenous infusions: saline; aspirin 15 mg/kg and heparin - 100 IU/kg bolus and 10 IU/kg infusion over one hour; 1.5 mg/kg rt-PA; 1.5 mg/kg rt-PA plus aspirin and heparin; 4.5 mg/kg rt-PA; 0.5 mg/kg Sak; 0.5 mg/kg Sak plus aspirin and heparin and 1.5 mg/kg Sak. Bleeding times were determined 30 and 15 min before and 5, 15, 30 and 60 min after the administration over one min of saline, rt-PA or Sak, by simultaneously severing a nail cuticle (CBT) and by puncturing the ear (EBT). Bleeding times were unaffected by saline and by both doses of Sak in monotherapy. Heparin-aspirin and low dose rt-PA significantly lengthened EBT but not CBT. Both CBT and EBT were significantly prolonged (to a mean of > 4 times pretreatment at 5 min) after high-dose rt-PA and after the combined administration of heparin and aspirin with either Sak or tr-PA. rt-PA provoked significantly longer bleeding than Sak in the CBT (p = 0.001; mean estimated difference = 23 min), but not in the EBT. rt-PA but not Sak degraded plasma fibrinogen dose-dependently. CBT correlated inversely with fibrinogen (r= -0.66, p=0.001) but EBT did not.

CONCLUSION

At equivalent doses Sak displays a significantly higher fibrin specificity and prolongs bleeding time less than rt-PA, particularly in the nail cuticle bleeding time model in which larger vessels are injured that require fibrinogen for hemostasis.

Thrombolytic therapy of peripheral arterial occlusion with recombinant staphylokinase

BACKGROUND

Recombinant staphylokinase (STAR) induces fibrin-specific coronary artery recanalization in patients with evolving myocardial infarction. The present pilot study evaluates its thrombolytic efficacy, safety, fibrin specificity, and immunogenicity in patients with peripheral arterial occlusive disease.

METHODS AND RESULTS

Thirty patients (37 to 86 years of age) with angiographically documented thromboembolic peripheral arterial occlusion of recent origin (21 +/- 5.5 days, mean +/- SEM) were treated with heparin and intra-arterial STAR given as a 1-mg bolus followed by a 0.5-mg/h infusion in 20 patients or as a 2-mg bolus followed by a 1-mg/h infusion in 10 subsequent patients. With 7.0 +/- 0.7 mg STAR infused over 8.7 +/- 1.0 hours, recanalization was complete in 25 patients, partial in 2, and absent in 3. Two major hemorrhagic complications occurred: one fatal hemorrhagic stroke and one hypovolemic shock caused by bleeding at the angiographic puncture site. Administration of STAR did not induce fibrinogen breakdown or a significant prolongation of template bleeding time. STAR-neutralizing activity and anti-STAR IgG were low at baseline, increased markedly from the second week on, and remained elevated for several months.

CONCLUSIONS

Intra-arterial administration of STAR restores vessel patency in patients with peripheral arterial occlusion in the absence of fibrinogen degradation.

A randomized trial of recombinant staphylokinase versus alteplase for coronary artery patency in acute myocardial infarction. The STAR Trial Group

BACKGROUND

Recombinant staphylokinase (STAR) was shown recently to offer promise for coronary arterial thrombolysis in patients with evolving myocardial infarction. The present multicenter randomized open trial was designed to assess the thrombolytic efficacy, safety, and fibrin specificity of STAR relative to accelerated alteplase (recombinant tissue-type plasminogen activator [RTPA]).

METHODS AND RESULTS

One hundred patients with evolving myocardial infarction of < 6 hours' duration and with ST-segment elevation were allocated to accelerated and weight-adjusted RTPA over 90 minutes (52 patients) or to STAR (the first 25 patients to 10 mg and the next 23 patients to 20 mg given intravenously over 30 minutes). All patients received aspirin and intravenous heparin. The main end points were coronary artery patency and plasma fibrinogen levels at 90 minutes. Thrombolysis in Myocardial Infarction (TIMI) perfusion grade 3 at 90 minutes was achieved in 62% of STAR patients versus 58% of RTPA patients (risk ratio, 1.1; 95% CI, 0.76 to 1.5). With 10 mg STAR, TIMI grade 3 patency was 50% (risk ratio, 0.86; 95% CI, 0.54 to 1.4 versus RTPA); with 20 mg STAR, it was 74% (risk ratio, 1.3; 95% CI, 0.90 to 1.8 versus RTPA). Residual fibrinogen levels at 90 minutes were 118 +/- 47% (mean +/- SD) of baseline with STAR and 68 +/- 42% with RTPA (P < .0005). STAR therapy was not associated with an excess mortality or electric, hemorrhagic, mechanical, or allergic complications. However, patients developed antibody-mediated STAR-neutralizing activity from the second week after STAR treatment. As an addendum to the randomized study, 5 patients were given 40 mg STAR over 30 minutes, resulting in TIMI perfusion grade 3 at 90 minutes in 4 patients without fibrinogen breakdown (residual levels at 90 minutes of 105 +/- 8% of baseline).

CONCLUSIONS

STAR appears to be at least as effective for early coronary recanalization as and significantly more fibrin-specific than accelerated RTPA in patients with evolving myocardial infarction.

High yield production and purification of recombinant staphylokinase for thrombolytic therapy

Recombinant plasmids were constructed in which the signal sequence of the sak42D and the sakSTAR staphylokinase genes were replaced by an ATG start codon and which express staphylokinase under the control of a tac promoter and two Shine-Dalgarno sequences in tandem. Induction of transfected E. coli TGl cells in a bacterial fermentor produced intracellular staphylokinase representing 10 to 15% of total cell protein. Gram quantities of highly purified recombinant staphylokinase were obtained from cytosol fractions by chromatography, at room temperature, on SP-Sepharose and on phenyl-Sepharose columns, with yields of 50 to 70 percent. The material, at a dose of 4 mg/kg, did not produce acute reactions or affect body weight in mice. Intravenous administration of 10 mg SakSTAR over 30 minutes in five patients with acute myocardial infarction induced complete coronary artery recanalization, without associated fibrinogen degradation. However, neutralizing antibodies appeared in the plasma of all patients within 12 to 20 days. Thus, the present expression and purification method for recombinant staphylokinase yields large amounts of highly purified mature protein (approximately 200 mg per liter fermentation broth) suitable for a more detailed clinical investigation of its potential as a thrombolytic agent.

Is BCG vaccination against tuberculosis still indicated?

More than 70 years after the introduction of BCG vaccination into clinical practice many questions remain to be answered. Major trials produced conflicting results regarding the degree of protection of this vaccine against tuberculosis. Several factors which may contribute to the inconsistent results of these trials, are discussed. In developing countries continuation of routine BCG vaccination of infants is highly recommended considering the ease of administration, low cost, wide availability and safety on the one hand and the protection provided particularly against haematogenous spread of tuberculosis on the other hand. In developed countries the vaccine is reserved for high risk groups since the prevalence of tuberculosis in the general population declined dramatically during the past decades. However, as the incidence of tuberculosis in the Western world no longer decreases steeply and indeed increases again in some countries, and because (para-) medical personnel risks to be among the prime victims of this re-emergence of tuberculosis, rigorously sustained preventive measures to protect this professional category deserve renewed interest. Among those, BCG vaccination can be considered, especially in case of a high prevalence of multidrug-resistant tuberculosis, but also for the Belgian situation with a high degree of non-immune health care workers. Therefore, we believe that BCG vaccination still has a future.